In a Telecommunication terminology, when computer devices share or exchange its data via data-link, we say computers are connected to each other. These connection could be via wired or wireless media. Each communication point between two devices are called network nodes where data transmit from one point to the other. These nodes are hosts like computers, mobile devices servers and network hardware as well. Computer networks exchange enormous amount of data in the form of applications, information and services via local workgroup, intranet and internet and shared devices could be computers, printers, servers, fax, mobile devices and others. Every single piece of data is transmitted in the form of signal and these signal are carried away via transmission media. There are some communications protocols or algorithms are used to route the network traffic, so that the data can be transmitted as early as possible to the destination end. Networks can be divided into...